bowel obstruction `(1B)

Question 1

Bowel obstruction is a ….. obstruction of the GI trac

Answer 1

mechanica

Question 2

Vessel occlusion in strangulated obstruction occurs due to …. pressure

Answer 2

intramural pressure e.g. hernia

Question 3

absence of vessel occlusion is called what?

Answer 3

simple obstruction

Question 4

Causes of bowel obstruction can be divided into what 3 categories?

Answer 4

luminal, intramural and extramural

Question 5

Luminal causes of bowel obstruction include

Answer 5

foreign object, faeces, gallstone ileus, large polyp

Question 6

Intramural causes of bowel obstruction include

Answer 6

strictures (diverticulitis, Crohns), Intussusception, infarction and tumours

Question 7

Bowel obstruction causes by Intussusception can be suspicious of …… in adults

Answer 7

tumour

Question 8

Extramural causes of bowel obstruction include

Answer 8

adhesions, incarcerated hernia, Volvulus, compressions (due to tumour in a neighbouring organ)

Question 9

Adhesions which cause extramural bowel obstruction can be caused by what conditions

Answer 9

surgery, IBD, or congenital bands

Question 10

Adhesions and strangulated hernia don’t tend to affect which bowel (small or large) and why

Answer 10

large bowel and because it is tethered in place

Question 11

Volvulus typically occur in what regions of the bowel

Answer 11

sigmoid, caecal or small bowel

Question 12

What is a common cause of large bowel obstruction

Answer 12

colorectal cancer

Question 13

Other common causes of bowel obstruction

Answer 13

Volvulus and diverticulitis

Question 14

Ileus and pseudo-obstruction are reduced bowel motility in the absence of …… obstruction

Answer 14

mechanical

Question 15

Where does paralytic ileus occur

Answer 15

small bowel

Question 16

Paralytic ileus results from…?

Answer 16

neurohormonal factors

Question 17

The stress of surgery or systemic illness usually causes

Answer 17

paralytic ileus

Question 18

What is the mainstay of treatment for paralytic ileus

Answer 18

conservative management

Question 19

Another name for pseudo-obstruction when acute is

Answer 19

Ogilvie syndrome

Question 20

Pseudo-obstruction affects which bowel

Answer 20

large bowel

Question 21

One typical cause of pseudo-obstruction is increase … or decrease… and it can be cause by what medications in what conditions

Answer 21

increased sympathetic tone of decrease parasympathetic tone and it can be caused by anticholinergics such as antiparkinsonism drug (trihexyphenidyl) which is important especially in old people

Question 22

Pseudo-obstruction can be decompressed with?

Answer 22

colonoscopy

Question 23

4 cardinal symptoms of bowel obstruction

Answer 23

vomiting, abdominal distension , constipation and abdominal pain

Question 24

Signs of bowel obstruction on examination

Answer 24

abdominal tenderness, tympanic percussion (unlike shifting dullness in ascites this is usually due to obsipation where there is an inability to pass gas or flatus )

Question 25

Tinkling bowel sounds is usually a a sign of ..?

Answer 25

large bowel obstruction and pseudo-obstruction and no bowel sounds in small bowel obstruction

Question 26

Other signs on examination can include ..?

Answer 26

hernia and surgical scars (adhesions )

Question 27

Complications of obstructed bowel include

Answer 27

bacterial translocation and sepsis

Question 28

Which bowel obstruction tends to occur much sooner and has higher risk of perforation

Answer 28

large bowel obstruction

Question 29

Blood in investigation; FBC may show? U&E may show? And lactate will be low or high and why?

Answer 29

fbc may show anaemia or infection, U&E may show dehydration and low K due to vomiting, lactate may be high due to bowel ischaemia

Question 30

Other bloods include?

Answer 30

Lfts, amylase/lipase , preop group and save

Question 31

Imaging wise what does standing AXR show

Answer 31

may show fluid level

Question 32

Standing CXR may show

Answer 32

subdiaphramtic air collection and pockets of gas especially in perforation

Question 33

What is gold standard and what does it show?

Answer 33

abdo pelvis CT with contrast and it shows transitions zones beyond which there is no contrast and in strangulation there may be bowel wall thickening and or poor iv contrast uptake

Question 34

In AXR of large bowel what is the typical diameter of the bowel after dilation?

Answer 34

6cm

Question 35

What is the surface of the large bowel called and in an obstruction is there complete or incomplete surface markings across the surface?

Answer 35

haustra and incomplete

Question 36

in AXR of small bowel what is the typical diameter of the bowel after dilation?

Answer 36

4cm

Question 37

What is seen in sigmoid Volvulus and what anatomical landmarks?

Answer 37

coffee bean v shaped from the LIF to the RUQ

Question 38

What is the surface of the small bowel called and in an obstruction is there complete or incomplete surface markings across the surface?

Answer 38

valvulae conniventes and incomplete

Question 39

Endoscopy is indicated for?

Answer 39

suspected malignancy and therapeutic relief of sigmoid Volvulus

Question 40

Absolute indications for immediate surgery include?

Answer 40

generalised peritonitis, caecum >10cm, irreducible hernia and perforation